Minimum components for PCB Arduino UNO assuming the microcontroller is connected to a computer with: SparkFun FTDI Basic Breakout - 5V You will need to decide if you want to use a vertical or horizontal header to connect the FTDI breakout board to the microcontroller.

Gas Sensors SEN-10916 SENSORM-TH_SPARKFUN_MQ-8 LCSC Part Number: C2614327 JLCPCB Part Class: Extended Part Manufactured by SparkFun Electronics

Gas Sensors SEN-09404 SENSORM-TH_SPARKFUN_MQ-4 LCSC Part Number: C2614326 JLCPCB Part Class: Extended Part Manufactured by SparkFun Electronics

Gas Sensors SEN-09403 SENSORM-TH_SPARKFUN_MQ-7 LCSC Part Number: C2614328 JLCPCB Part Class: Extended Part Manufactured by SparkFun Electronics

Gas Sensors SEN-08880 SENSORM-TH_SPARKFUN_MQ-3 LCSC Part Number: C2614329 JLCPCB Part Class: Extended Part Manufactured by SparkFun Electronics

RedBoard Artemis ATP is Apollo3 Transceiver; Bluetooth® 5 2.4GHz Evaluation Board, No 3D

SparkFun's Qwiic Connect System uses 4-pin JST connectors to quickly interface development boards with sensors, LCDs, relays and more. Connector Header Surface Mount, Right Angle 4 position 0.039" (1.00mm)